<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>Title</title>
</head>
<body>
    <script type="text/javascript">
        setTimeout(()=>{
                console.log(111111111111111111);
                setTimeout(()=>{
                    console.log(2222222222222222);
                    setTimeout(()=>{
                        console.log(3333333333333333)
                    },3000)
                },2000)
        },1000)
    </script>
</body>
</html>
